This invention relates generally to intraocular lenses and deals more specifically with an improved arrangement and method for securing such lenses within the eye.
Following removal of the natural lens during cataract surgery, an artificial intraocular lens is often implanted in the eye. In order to prevent adverse effects such as distortion of the vision, it is necessary for the implanted lens to be securely retained in the correct position in the pupillary region. However, due to the drawbacks of the lens securing devices that have been proposed in the past, it is not unusual for the lens to become dislocated, thereby causing discomfort, visual distortion, and other harmful effects.
At present, the lens is normally implanted immediately in front of the iris and is typically provided with projecting bars or loops which are placed loosely behind the iris. Since the bars and loops fit loosely behind the iris, they are able to pass forwardly through the pupillary aperture when dilation occurs. Consequently, the lens becomes completely disconnected from the iris and is able to assume an improper position in the eye. Although eye drops have been used to combat this problem by controlling dilation of the iris, such a solution is inconvenient at best.
It has also been proposed to fix the lens to the iris by means of a suture or a metal clip or hook, either alone or together with loops and bars such as those described previously. Aside from the additional time and difficulty involved in performing the surgery, this proposal has not successfully eliminated the problem of dislocation of the lens. For practical reasons, the suture or clip is ordinarily applied only to one side of the lens so that the opposite side is still able to become improperly oriented with respect to the iris, particularly when the pupil becomes dilated.
It is the primary object of the present invention to provide an improved intraocular lens structure which may be firmly secured in the pupillary region of the eye.
Another object of the invention is to provide an intraocular lens structure which may be easily implanted and thereafter secured in the appropriate position during the postoperative period. Significantly, the lens need not be secured at the time of surgery but can instead be fixed in place at a later time after the surgeon has had an opportunity to confirm that the lens is positioned correctly.
A further object of the invention is to provide a lens of the character described which includes a pair of arms that coact with the lens to pinch the iris in a manner preventing dislocation of the lens, even during dilation.
Still another object of the invention is to provide a lens of the character described which is economical to manufacture and easy to implant and secure within the eye.
A further object of the invention is to provide a method of placing and securing an intraocular lens in the eye.
Other and further objects of the invention, together with the features of novelty appurtenant thereto, will appear in the course of the following description.